The present invention relates to a laundry washing machine.
More in particular, the present invention relates to a front-loading home laundry washing machine, to which the following description refers purely by way of example without this implying any loss of generality.
As is known, a front-loading home laundry washing machine generally comprises: a substantially parallelepiped-shaped outer boxlike casing structured for resting on the floor; a substantially horizontally-oriented and approximately cylindrical washing tub which is usually suspended in floating manner inside the casing, with the front mouth directly facing a laundry loading/unloading through opening realized in the front wall of the casing; a substantially cylindrical, cup-shaped rotatable drum structured for housing the laundry to be washed, and which is fitted inside the washing tub with the concavity facing the laundry loading/unloading opening, and is supported by the washing tub in axially rotatable manner so as to be able to freely rotate inside the washing tub about its substantially horizontally-oriented, longitudinal axis; a substantially cylindrical, elastically-deformable bellows which watertight connects the front mouth of the washing tub to the laundry loading/unloading opening formed in the front wall of the casing; a porthole door which is hinged to the front wall of the casing to rotate to and from a closing position in which the door closes the laundry loading/unloading opening in the front wall of the casing for watertight sealing the washing tub; and an electrically-powered motor assembly which is structured for driving into rotation the rotatable drum about its longitudinal axis inside the washing tub.
This type of laundry washing machine furthermore comprises: a detergent dispenser which is located inside the boxlike casing, immediately above the washing tub, and is structured for selectively feeding into the washing tub, according to the washing cycle manually-selected by the user, a given amount of detergent, softener and/or other washing agent suitably mixed with fresh water arriving from the water mains; a fresh-water supply circuit which is structured for selectively drawing fresh water from the water mains according to the washing cycle manually-selected by the user, and channelling said fresh water to the detergent dispenser or directly to the washing tub; and finally an appliance control panel which is generally located on the front wall of the casing, above the laundry loading/unloading opening, and is structured for allowing the user to manually select the desired washing-cycle.
In addition to the above, high-end front-loading laundry washing machines may optionally have an internal water softening device which is located along the fresh-water supply circuit, and is structured to selectively reduce the hardness degree of the tap water channelled towards the detergent dispenser and the washing tub. The use of softened water during the washing cycle, in fact, significantly improves cleaning performances.
More in detail, the water softening device is generally internally provided with a given amount of ion-exchange resins which are capable of retaining the calcium and magnesium ions (Ca++ and Mg++) dissolved in the water flowing through the same water softening device, so as to reduce the hardness degree of the tap water directed towards the detergent dispenser and the washing tub.
In addition to the above, since the water softening capabilities of the ion-exchange resins are used to quickly drop away after a limited number of washing cycles, this high-end laundry washing machines are generally provided with an internal reservoir of salt (NaCl) to be used for selectively producing some brine (i.e. salt water) which is periodically channeled into the water softening device to regenerate the ion-exchange resins located therein. Salt water, in fact, is able to remove from the ion-exchange resins the calcium and magnesium ions previously combined/fixed to said resins.
WO2013/160211 discloses a front-loading home laundry washing machine wherein the salt to be used in the regeneration process of the ion-exchange resins is stowed into a cup-shaped container which has a mesh structure and is located into a regeneration-agent drawer which, in turn, is fitted in manually extractable manner on front wall of the casing, beside the detergent drawer of the detergent dispenser. The brine formed into the regeneration-agent drawer is fed to the water softening device by means of an electric pump assembly that sucks the brine directly from the bottom of regeneration-agent drawer.
Unluckily the hydraulic fittings necessary to floatingly connect the suction of pump assembly directly to the bottom of the regeneration-agent drawer are rather costly and significantly increase the overall production costs of the laundry washing machine.
Furthermore, the pump assembly does not allow a prompt and precise dosage of the brine channeled into the water softening device, because the amount of brine accumulating on the bottom of regeneration-agent drawer per time unit is highly dependent on the compactness of the salt grains contained in the regeneration-agent drawer.
Lastly, when the user pours the salt into the cup-shaped container, some salt grains may accidentally fall on the bottom of the regeneration-agent drawer and block up the suction of the pump assembly with all problems that follows.